Light-emitting components, in particular LEDs or organic light-emitting diodes (OLED), are being used increasingly widely for example for general lighting, for example as flat light sources, or as a representation device, for example in the form of displays or signaling devices.
An OLED, for example, may include an anode and cathode and an organic functional layer system between them. The organic functional layer system may include one or more emitter layers, in which electromagnetic radiation is generated, a charge carrier pair generation layer structure respectively consisting of two or more charge carrier pair generation layers (“charge generating layer”, CGL) for charge carrier pair generation, and one or more electron barrier layers, also referred to as hole transport layer(s) (HTL), and one or more hole barrier layers, also referred to as electron transport layer(s) (ETL), in order to direct the flow of current.
LEDs and OLEDs are at present practically available only in two-dimensional shape, so to speak in 2D, i.e. flat, for example as flat keyboards, or in sheet shape and flexible, so to speak in 2.5D. 2.5D refers to flat OLEDs consisting of flexible substrates, which up to a certain extent can be bent nondestructively, so that for example a curved OLED may be formed. OLEDs on arbitrarily shaped substrates with genuine 3D surfaces, and in particular 3D luminous faces, are to date substantially unknown. A 3D surface in the context of this application may, for example, have a non-constant curvature variation or two or more curvatures in at least two different spatial directions.
The basic problem in this case involves homogeneous deposition of the thin functional organic layers on nonplanar substrates. For high-power OLEDs, organic layer stacks are generally applied by physical vapor deposition. These are so-called line-of-sight methods, which allow homogeneous surface-wide coatings for flat (and possibly for moderately curved) substrates. For coating the surface of a complex 3D object, however, the existing methods are unsuitable since uncoated regions are left because of shadowing, and/or the coating becomes increasingly inhomogeneous.
Furthermore, for the function of an OLED it is important to apply the organic functional layers onto the substrate with an accurately defined thickness, since otherwise the performance of the OLED is not particularly good. In particular, undesired lateral layer thickness variations lead to undesired luminance gradients. Because of the different orientation of different surface regions of 3D substrates relative to the coating source, however, such layer thickness variations occur. Currently known methods are therefore not suitable for the production of OLEDs on 3D surfaces even when the above-explained case of shadowing of subregions is prevented.
As an alternative thereto, it is known to form 3D OLEDs by assembling a plurality of 2D OLEDs to form 3D bodies. For example, a cube may be formed from six square 2D OLEDs. In this case, however, non-luminous edge regions (the edges of the 2D OLEDs) remain at the edges of the 3D object, and only angular 3D bodies which can be assembled from planar surfaces are possible.
DE 10 2007 060 585 A1 discloses a 3D OLED which has a special shape, although the way in which the above-explained problems are solved, particularly in terms of deposition of the organic functional layers, is not shown.
It is an object of the present disclosure to provide a light-emitting module which has a three-dimensional luminous face, for example a complex three-dimensional luminous face, which has a mechanically flexible luminous face, for example an elastically deformable luminous face and/or can be produced simply and/or economically, for example with a low system complexity of a system for producing the optoelectronic module.
It is another object of the present disclosure to provide a method for producing a light-emitting module, which can be carried out simply and/or economically, for example with a low system complexity of a system for producing the optoelectronic module, and/or makes it possible for the optoelectronic module to have a three-dimensional luminous face, for example a complex three-dimensional luminous face, and/or a mechanically flexible luminous face, for example an elastically deformable luminous face.